Login or Register to Ask a Question and Join Our Community


Shell Programming and Scripting

awk getline 8 times and if $3 = 8 when subtracted from 1st line,print

Login to Discuss or Reply to this Discussion in Our Community

 
Thread Tools Search this Thread
Top Forums Shell Programming and Scripting awk getline 8 times and if $3 = 8 when subtracted from 1st line,print
# 1  
Old 08-16-2013
awk getline 8 times and if $3 = 8 when subtracted from 1st line,print
I have kind of a strange one here. I have a file of consecutive /24 ip blocks. If there are 8 consecutive ip blocks which represent a /20 then I need to print the first line. I played around and did not get the results I need, especially when considering that the highest $3 will be is 255 and then start over to 0.

Here is a sample file
Code:
10.71.192.0
10.71.193.0
10.71.194.0
10.71.195.0
10.71.196.0
10.71.197.0
10.71.198.0
10.71.199.0
10.78.176.0
10.78.177.0
10.78.178.0
10.78.179.0
10.90.25.0
10.90.26.0
10.122.232.0
10.122.233.0
10.122.234.0
10.122.235.0
10.122.236.0
10.122.237.0
10.122.238.0
10.122.239.0
10.144.251.0
10.144.252.0
10.144.253.0
10.144.254.0
10.144.255.0
10.145.0.0
10.145.1.0
10.145.2.0

What I need to see output is:
Code:
10.71.192.0
10.122.232.0
10.144.251.0

I tried something like this but did not get good results
Code:
nawk -F"." '{p=$0; v=$3; getline;getline;getline;getline;getline;getline;getline;getline; d=$3 - v} d = 8 {print p}' myfile

# 2  
Old 08-17-2013
First things first: 8 consecutive /24 blocks do not represent a /20 block but a /21 block and only if the lowest third number of the consecutive /24 ranges is divisible by 8.
# 3  
Old 08-17-2013
Typo, sorry that is correct a /21.
Last edited by numele; 08-17-2013 at 10:12 AM..
# 4  
Old 08-17-2013
Your sample output is not correct!

Try
Code:
awk  '{if (++C[$1$2($3-$3%8)] == 8) print $1,$2,($3-$3%8),$4}' FS="." OFS="." file
10.71.192.0
10.122.232.0

These 3 Users Gave Thanks to RudiC For This Post:
numele RavinderSingh13 Scrutinizer
# 5  
Old 08-17-2013
Nice solution RudiC !

I think it would be better to separate the fields in the index to avoid overflow between ranges.
I made an adaptation to your solution so that the CIDR prefix becomes variable:
Code:
awk -F. -v cp=21 'BEGIN{s=2^(24-cp)}{r=$1 FS $2 FS $3-$3%s FS $4} ++C[r]==s{print r}' file

Last edited by Scrutinizer; 08-17-2013 at 03:06 PM..
These 2 Users Gave Thanks to Scrutinizer For This Post:
numele RudiC
# 6  
Old 08-17-2013
Above was a "sketch", a "draft", and I was thinking about making it a bit more flexible myself. Thank for your proposals; separating the index fields is a good one, as is the variable bit depth for the netmask... Although the requestor asked for 8; we just infer he wants to see if that subnet is "full".
Last edited by RudiC; 08-17-2013 at 03:15 PM..
# 7  
Old 08-17-2013
Thank you both, worked very well.
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

awk file subtracted by a fix value - conditioned

Hi all... i have been trying to make this work but I have been failing for 6 hours .. I know it should be something simple that I am missing to it would be great if you can help me ... I want to subtract a fixed value (lets set 1) from any value >=1 from the whole file my file looks like ... (4 Replies)
Discussion started by: A-V
4 Replies

2. Shell Programming and Scripting

awk to print the line that matches and the next if line is wrapped

I have a file and when I match the word "initiators" in the first column I need to be able to print the rest of the columns in that row. This is fine for the most part but on occasion the "initiators" line gets wrapped to the next line. Here is a sample of the file. caw-enabled ... (3 Replies)
Discussion started by: kieranfoley
3 Replies

3. Shell Programming and Scripting

How to print a particular character n number of times in a line??

hi, Is it possible to print a particular character n number of times in a line? for example. i am print the following line using echo command.. echo "files successfully moved" i want to count the number of characters that are been displayed. i am doin it using echo "files... (8 Replies)
Discussion started by: Little
8 Replies

4. Shell Programming and Scripting

awk script -print line when $2 > $2 of previous line

Hi all, From a while loop I am reading a sorted file where I want to print only the lines that have $1 match and $2 only when the difference from $2 from the previous line is > 30. Input would be like ... AN237 010 193019 0502 1 CSU Amoxycillin AN237 080 ... (2 Replies)
Discussion started by: gafoleyo73
2 Replies

5. Shell Programming and Scripting

print whole line if the 1st field contains...

i want to print lines in a file that the 1st field of each line has a Date shape such: yy/mm/dd or on the other hand contains slash "/" . (1 Reply)
Discussion started by: oreka18
1 Replies

6. Shell Programming and Scripting

GetLine fn always giving last line of the file

Hi, Its bit urget for me to complete. pls help me. I am parsing 2 file 1. INDATA(Data file) 2. GRPFIL(Reference) every record in INDATA should be verified with GRP_DATA. I am seeing the output from only the last line of ref file, its not searching all the lines. INDATA sample... (1 Reply)
Discussion started by: hyperion.krish
1 Replies

7. Shell Programming and Scripting

awk print header as text from separate file with getline

I would like to print the output beginning with a header from a seperate file like this: awk 'BEGIN{FS="_";print ((getline < "header.txt")>0)} { if (! ($0 ~ /EL/ ) print }" input.txtWhat am i doing wrong? (4 Replies)
Discussion started by: sdf
4 Replies

8. Shell Programming and Scripting

awk print the next line on the current line

Ok I have a file with hundreds of lines, four columns, space delimited, TESTB.TXT for example TESTB.TXT --- AA ZZ 12 34 BB YY 56 78 CC XX 91 23 DD VV 45 67 --- I want a new file that has 7 columns, the first four are identical, and the next 3 are the last three of the next line...so... (5 Replies)
Discussion started by: ajp7701
5 Replies

9. Shell Programming and Scripting

print any required line by its line no using awk and its NR variable

how to print any required line by its line no using awk and its NR variable for eg: ------------ 121343 adfdafd 21213sds dafadfe432 adf.adf%adf --------------- requied o/p if give num=3 it print: 21213sds -------------------------------------- (2 Replies)
Discussion started by: RahulJoshi
2 Replies

10. Shell Programming and Scripting

AWK print a character many times

How can I print a '-' on the same line within awk, say 50 times, without actually typing '-' 50 times? Cheers (3 Replies)
Discussion started by: dbrundrett
3 Replies
Login or Register to Ask a Question